A Ni(II) derivative incorporating tetradentate Schiff base precursor: Structure, spectral, electrochemical and DFT interpretation.

Abstract The Ni(II) derivative, namely Ni [L]⋅ClO 4 (1) is afforded incorporating the Schiff base precursor, (HL) = [2-((E)-(2-(2-aminoethylamino)ethylimino)methyl)-6-methoxyphenol]. Single crystal X-ray structure reveals that in 1 , the central Ni(II) atom is surrounded by N 3 O donor set and possesses on a distorted square-planar environment. EPR spectra confirms that compound 1 is diamagnetic due to square-planar geometrical nature having a spin state S = 0. DFT computational studies are in good agreement with the structural and spectral data. The electrochemical study of compound 1 shows one quasi-reversible oxidative peak at 0.92 V vs Ag/AgCl due to a redox couple of Ni(II)/Ni(III); nd a weak oxidation peak at −0.72 V vs Ag/AgCl which might be assigned to Ni(I/II) couple. Highlights • Mononuclear NiII complex with a tetradentate Schiff base precursor is afforded. • Interestingly, three different N atoms of N 3 O donor set are coupled to NiII atom. • EPR study confirms the diamagnetic nature of the compound having a spin state S = 0. • TD-DFT computation supports the electronic nature of metal ion. • Redox study affirms one quasi-reversible oxidative peak of Ni(II)/Ni(III) and a weak oxidative peak of Ni(I/II) couple. [ABSTRACT FROM AUTHOR]